The present invention relates generally to abraiding through the use of rotary lapping systems, and is specifically directed to the use and configuration of grinding pads, called tesserae, which produce a positive lift effect in high speed lap grinding.
Future generations of orbiting telescopes used for astronomy, information collection and transmission, and power transmission will require very large segmented mirrors. The telescope designs will necessarily make use of highly aspheric mirrors.
While prior art rotary lapping systems are used to remove material from a variety of workpieces, prior art systems are not effective in producing large lightweight, odd-shaped, infrared quality aspheric mirrors, and other optical elements, which are manufactured through a succession of grinding and polishing with rotary lapping systems. A review of optical surfacing techniques indicates that two-thirds of the manufacturing time is spent polishing out subsurface damage from grinding.
There exists a need to process large sections of aspheric optical systems in a rapid and efficient manner. While optical surface tolerances are less difficult to meet in infrared systems, eventually the next generation of space telesopes will require quality suitability for visible-spectrum use.
In view of the foregoing discussion it is apparent that there currently exists the need for a rotary lapping system which has an ability to hydroplane above a work surface on the abrasive slurry liquid, to effectively, grind, aspheric workpieces. The present invention is directed towards satisfying that need.